1G 3g booster in 1g dsm

[SasaniFab]

Two years ago I did the 3000gtvr4 brake swap on my 1g which included swapping over the master and booster, none of which is necessary, it’s comes down to pedal stiffness and what you like in regards to pedal effort. After going back to the 1g twin calipers I decided to go back to the original sized master while keeping the 3g booster. What I realized and what turned out to be a major oversight on my part is the pushrod free play on the booster, I never adjusted anything when I swapped everything over and now I’m realizing I may have had slight drag on the brakes the entire time. The 3g master piston has a lot of clearance internally when compared to the 1g master. To get my brakes working correctly I had to turn the pushrod nut in all the way to get the correct free play. Does everybody check their booster free play when setting up their brakes?

 

[talon77]

I agree that the booster pushrod free play needs to be checked when the 3g Master Cylinder is installed. I did not initially check free play between the booster pushrod and the 3g MC when I first installed the MC (with STOCK booster); I just bolted everything together and made fine adjustments at the brake pedal. However, when I went back to re-check things, I discovered that there is indeed excessive freeplay if everything is installed as-is with no adjustments. I ended having to turn the booster pushrod counter-clockwise out to slightly elongate it, so that the freeplay met dsm OEM specs, per the FSM (ie: not too big of a gap between the booster pushrod and the MC; and not too tight as to allow the two contact surfaces to touch and cause brake drag).

 

[troppo loungo]

I am gearing up to perform ABS delete on my 93 1G. Was considering upgrading to the 3G master at the same time. What will be the result with the stock 2 piston calipers if 1) I upgrade to the 3G master on stock booster 2) I upgrade to both 3G master and 3G booster. I assume the 3G booster has more vacuum volume and/or assist? I do a fair bit of lapping days.

 

[ist dwa]

I have installed two 3g boosters. Both needed to be adjusted to get it just right.

 

[troppo loungo]

Thanks for the info regarding the 3G booster adjustment that is needed.
Looking for experience on pedal feel and performance with stock 2 piston front calipers if; 1) I upgrade to the 3G master only on the stock booster and 2) I upgrade to both 3G master and 3G booster.

Thanks,